<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8" />
		<meta name="viewport" content="width=device-width, initial-scale=1">
		<title>web</title>
		<script type="text/javascript">
			var n1=12;
			var n2=1.23;
			var n3=3.98;
			var n4=12.01;
			
			var n5=Math.ceil(n4);	//天花板函数  向上取整
			
			var n5=Math.max(n1,n4);		//取得是两个数的最大值
			
			var n5=Math.min(n3,n1);		//返回是两个数的最小值
			
			var n5=Math.pow(n1,n2);		//返回n1的n2次方
			
			var n5=Math.round(n4);		//向下取整
			
			// var n5=Math.random();		//返回0-1之间的随机数
			
			alert(n5);
		</script>
	</head>
	<body>
		
	</body>
</html>